Crushing apparatus



Jan 6, 1931. N. D. LEVIN CRUSHING APPARATUS Filed June 1, 1927 Patented .Jan. 6, 1931 8 UNITED STATES PATENT OFFICE NILS D. LEVIN, OF COLUMBUS, OHIO, ASSIGNOR TO THE JEFFREY MANUFACTURING COMPANY, OF COLUMBUS, OHIO, A CORPORATION OF OHIO ORUSHING APPARATUS Application filed June 1,

The present invention relates to certain new and useful improvements in crushing apparatus of the type wherein the material to be crushed is brought into contact with a series of rapidly revolving heaters to be broken thereby.

Crushing machines of the general class to which my present invention relates, comprise a casing within which revolves a rotor having radially projecting hammers adapted to engage and pulverize fragments of material within the casing. In such machines the fineness of the roduct bears a direct relation to the speed c rotation of the pulverizing hammers. When such machines are designed for fine grinding, the pulverizing hammers are loosely mounted upon supporting rods which extend longitudinally of the rotor, reliance being had upon centrifugal force to hold them in radial projection. This method of support provides for the hammers a resilience which permits them to yield rearwardly to the shock of impact with large or excessively hard fragments, thus preventing undue strain upon the apparatus. l/Vithin recent years machines of this class have been applied to the reduction of coal, stone, or similar materials,

to relatively coarse products. When so applied the speed of rotation of the hammers must be reduced to such a degree that the centrifugal force generated is insuflicient to hold the hammers in operative position, and said hammers must be rigidly held in radial projection by theengagement of two or more of the longitudinal supporting rods. I have found that when two adjacent hammers in the same longitudinal row, contact with a large or hard object in the pulverizing chamber, the resultant strain tends to spread the hammers apart, thereby gradually expanding the rotor longitudinally of the supporting shaft with disastrous results. When the elements comprising the rotor are rigidly connected together to obviate the diiliculty above referred to, the entire mass tends to move as a unit, and to slip longitudinally of the shaft unless means is rovided to securely anchor them in fixed rel zition thereto.

It is the especial object of this invention to provide in a machine of the class described,

1927. Serial No. 195,757.

an improved rotor construction whereby is overcome the defect inherent in the construction heretofore commonly relied upon.

The means whereby I attain this object are fully set forth in the following specifications and illustrated in the accompanying drawing of which Fig. 1 is a transverse vertical section of a crushing machine having a rotor constructed 1n accordance with my present invention.

Fig. 2 is a sectional View of the machine illustrated in Fig. 1, taken along its central lon itudinal vertical plane.

ig. 3 is a transverse section of a modification of the rotor illustrated in Fig. 1.

Like numerals refer to similar parts in the several figures.

In the drawings I have illustrated one form of pulverizing machine to which my improved rotor may be applied. As here shown, the numeral 1 refers to a main supporting frame of generally rectangular form, upon which the operative parts of the apparatus are supported. End walls 2 and 3 are attached to the base frame 1 and between these end walls extend the breaker plate 4 and the curved back plate 5 which form opposite side walls of the pulverizing chamber. An upwardly extending outwardly inclined extension 6 of the back plate 5 provides a chute along which material may slide into the pulverizing chamber. Under some conditions of service longitudinally extending grate bars 7 may be supported upon suitable flanges of the end walls 2 and 3 to form a semi-cylindrical floor for the pulverizing chamber, the.

spaces between the grate bars 7 affording means of escape for the fully pulverized material, but such grate bars may be omitted without departure from the spirit of my invention.

Mounted upon the supporting frame 1 outside of the end walls 2 and 3, are the journal bearin s 8 and 9 wherein is journaled the shaft 10 w ich extends longitudinally of the machine through suitable openings in the end walls 2 and 3. The shaft 10 projects beyond the journal bearing 8, and to this shaft extension 11 may be connected, in any preferred manner, any convenient and suitable power devices whereby the shaft 10 may be caused to revolve. Mounted upon the shaft 10 in spaced relation longitudinally thereof, are a plurality of discs 12 and 13 having a series of apertures arranged in spaced relation to each other in a circle concentric with the shaft 10, through which extend the rods 14 parallel with the shaft 10. Upon the rods 14 are supported the pulverizing elements, preferably formed with three equally spaced arms 15, 16 and 17, each of which is pierced by an aperture adapted to engage one of the rods 14. 'The proportions of these parts are such that when in place two of the rods 14 will extend through two of the arms, as for example the arms 15 and 16, to hold the third arm 17 rigidly in radial extension beyond the periphery of the discs 12, to constitute a pulverizing hammer. The thickness of the pulverizing elements is equal to the longitudinal space between the discs 12, and filler blocks 18 of similar thickness are provided upon the rods 14.- in the spaces not occupied by pulverizing elements. At both ends the rods 14 are threaded, and fitted with nuts 19 which are drawn up tight to clamp the discs and hammers together forming a rigid rotor structure. The end discs 13 are provided with outwardly projecting annular flanges 20, concentric with the shaft 10, and the lining lates 21 closely fit around these annular anges 20 to prevent the escape of material from the pulverizing chamber and to protect the nuts 19 from its abrasive action.

Formed integral with the shaft 10, preferably near it middle, is a collar 22 which projects into the space between two adjacent discs 12, both of which it engages to hold the rotor from movement in either direction lonitudinally of the shaft. Suitable keys 23 xed to the shaft 10 engage key ways in the discs 12 and 13 to fix the rotor rotatively to the shaft 10.

It will be seen that in the rotor as illustrated, each hammer of each axially extending series is supported between a separate pair of discs and that the filler pieces between these pairs of discs are the same width as the hammers. Likewise collar 22 is of the same width as the hammers and filler pieces. With the parts assembled as shown, consequently, upon tightening nuts 19, the hammers and filler pieces are rigidly clamped between the discs and the series of discs at each side of collar 22 is rigidly clamped against the latter. It is to be noted that the discs are plane surfaced, and that the hammers are maintained in radial position under impact by means of their engagement with at east two of the tension rods.

In Fig. 3 of the drawing, I have shown a modified construction wherein the filler blocks 18 are omitted. In this construction the arms 24 and 25 of the pulverizing elements are of sufficient length to extend into close proximity with the next adjacent supporting rods thereby filling the space between the discs and serving in lieu of the filler blocks in the manner shown. 1

It is to be understood I do not limit myself to the precise construction here shown since the device may be subject to wide variation without departure from the spirit of my invention.

WVhat I claim is:

1. In a machine of the class described, a shaft, a series of plane surfaced discs coaxially mounted on the shaft, said discs being adjustable along the shaft relative to each other, means to prevent rotation of the discs relative to the shaft, a plurality of rods extending through aligned apertured in the discs, rigid radially extending hammers mounted on said rods between the discs, each hammer being engaged by at least two rods, nuts threaded on the ends of said rods whereb said disc may be drawn together to 0- amp the hammers rigidly between them, and abutment means on the shaft to prevent axial movement of the drawn-together discs relative thereto.

2. In a machine of the class described, a shaft, a series of plane surfaced discs eo-axially mounted on the shaft, said discs being adjustable along the shaft relative to each other, means to prevent rotation of the discs relative to the shaft, a plurality of rods extending through aligned apertures in the discs, axially extending series of rigid radially projecting hammers mounted on said rods, each hammer of each series being engaged by at least two of said rods between a separate pair of discs, filler pieces around free portions of the rods between the pairs of discs, nuts threaded on the ends of said rods whereby the discs may be drawn together to clamp the hammers and filler pieces rigidly between them, and abutment means on the shaft to prevent axial movement of the drawn-together discs relative thereo.

3. In a machine of the class described, a shaft having a rigid collar intermediate its ends, a series of plane surfaced discs co-axially splined on the shaft at each side of said collar, a plurality of rods extending through aligned apertures in the discs, axially extending series of radiall projecting hammers mounted on said ro s, each hammer of each series being engaged by at least two of said rods between a separate pair of discs, filler pieces on free portions of the rods between the pairs of discs, and nuts threaded on the ends of said rods whereby the discs of each series may be drawn together to clamp the hammers rigidly between them, each series of discs being thereby drawn tightly against said collar.

4. In a machine of the class described, a shaft having a rigid collar intermediate its ends, a series of plane surfaced discs co-axially splined on said shaft at each side of said collar, a plurality of rods extending through aligned apertures in the discs throughout the discs of both series, axially extending series 5 of radiall projecting hammers mounted on said rods etween the discs of each series and between the inmost discs of the two series, each of the hammers being engaged by at least two of said rods, the mner end of said hammers being of the same width as said collar, filler pieces of the same Width as the collar strung on free portions of the rods between adjacent series of discs, and nuts threaded on the ends of said rods whereby the discs of each series may be drawn together to clamp the hammers rigidly between them, each series of discs being thereby drawn tightly against said collar and against the inner ends of the hammers 29 mounted between the series.

In testimony whereof, I have hereunto set my hand.

NILS D. LEVIN. 

